A worker for the American Humane Association helps transport a Chihuahua seized at a Mississippi puppy mill to New York on Sunday. (See second item below.)

Better veterinary care and nutrition has led to an increase in the senior pet population, a Massachusetts veterinarian says, but the downside is that vets are seeing more animals with dementia.

Thomas M. Burns, hospital director of Cape Cod Veterinary Associates, told the website SouthCoastToday.com that while strange behavior may be caused by underlying medical conditions, the family pet could also be suffering from dementia, or cognitive dysfunction as the condition is called in veterinary medicine.

The signs are usually very noticeable.

Your dog might wake up in the middle of the night and pace back and forth in a frenzy.

Your cat might scratch in its litter box, and then relieve itself on the kitchen floor.

Burns said there is no known cause of this progressive disease. The list of possible sources reads like a medical textbook.

Joni Price, office manager at a Saginaw-area veterinary hospital, said she has noticed animal lovers postponing or canceling appointments in recent months because money is tight.

“We are seeing people treating their pets themselves and waiting longer to get them in to us,” said Price. “They’re just trying to buy over-the-counter things until it’s absolutely necessary to bring them in.”

Fetch takes a topical look at a variety of issues affecting pets, including the latest research results.. It seeks to provide useful information for Colorado pet owners and to spotlight the work of Colorado animal welfare groups.